The Supreme Court has ordered all Delhi-NCR governments to ensure strict implementation of GRAP Stage IV rules amid rising air pollution levels. The curbs will remain in place even if air quality index falls below the ‘severe plus’ mark of 450.

Residents in India's northern states woke up to another day of poor air quality on Tuesday, as a layer of dense fog shrouded most of the region, and pollution in the capital Delhi remained severe.

India's capital city of Delhi has virtually shut down as air pollution hit "severe plus" levels, according to Indian government officials in its pollution control authority.